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Q no :5(a) Define covalent bond. Explain formation of covalent bond in O2and N2molecules
The type of bond which is formed due to mutual sharing of electron is called covalent bond.Double Covalent Bond: When each bonded atom contributes two electrons two bond pairs are shared and a double covalent bond is formed. These bond pairs are indicated as double line between those atoms in the structure of such molecules the molecules lime oxygen (O2) gas and (C2 H2 ) show such type of double covalent bonds.Triple Covalent Bond : When each bonded atom contributes three electrons three bond pairs are involved in bond formation. This type is called covalent bond. Three smallines are used to indicate these three pairs of electron between those atoms in the molecules of such compounds the example of molecules having triple covalent bonds are nitrigen(N2) and ethyne(C2H2) N+xNx _________> : N:or N=N1, N2,By this mutual sharing of valence shell electrons each of the contributing atom attains the octet or nearest noble gas electronic configuration.
Q no: 5(B) Write down the properties of Ionic Compound?
The following are the propertise:1- Ionic compounds are mostly crystalline solids.2- Ionic compounds in solid state havenegligible electrical conductance but they are good conductors in solution and in the molten form3- Ionic compound have high melting and boiling point4- They dissolve easily in polar solvents like water. Water has high dielectric constant that weakens the attraction between ions.
Q no 6(A) Define Ionic or electrovalentbond and how sodium chloride and magnesium chloride are formed?
A Chemical bond which is formed due to complete transfer of electron from one atom to another atom is called ionic bond.The formation of NaCl is a good example of this type of bond. 2Na + Cl2 _______> 2NaClSodium Chloride is a simple compound formed from Sodium (z=11) and Chlorine (z=17). The ground state electronic configuraionof these elements is shown below The frame indicates electrons in valence shells of the elements Sodium has only one electron and Chlorine has seven electrons. Sodium being electropositiveelement has the tendency to lose electron and Chlorine being an electronegativeelement, has the tendency to gain electron.
Q no:6 (B) How a chemical bond is formed? Define the type of covalent bond and give example of each
Chemical bonds may be formed by complete transfer of electron; mutual sharing on by donation from an atom.Types of Covalent Bond: There are three types of Covalent bond1- Single Covalent bond2- Double Covalent bond3- Triple Covalent bond1) Single Covalent bond:When one electron is contributed by each bonded atom, one bond pair is formed and it forms a single covalent bond.Example:1) Hydogen2) ChlorineDouble Covalent bond: When each bonded atom contributes two electrons, two bond pairs are shared and a double covalent bond is formed.Example:1) Oxygen2) Ethane3) Triple Covalent bond When each bonded atom contributes there electrons, three bond pairs are involved in bond formation.Example:1)- Nitrogen2)- Ethyne
What are intermolecular force? Compare these with chemical bond forces with reference to HCL Molecule.
The forces that hold atoms in a compound are Chemical bonds. In addition to these strong bonding forces, relatively weak forces also exist in between the molecules Bonding with HCL:It requires about 17 Kj energy tobreak these intermolecularforces between one mole of liquid hydrogen molecules to convert it into gas.Whereas about 430 kjare required to break the Chemical bond between hydrogen and chlorine atoms in 1 mole of hydrogen chloride.
Define covalent bond. Explain formation of <gwmw class="ginger-module-highlighter-mistake-type-1" id="gwmw-15864192806510958945134">covalant</gwmw>bond in O2 and N4
The type of bond which is formed due to mutual sharing of electron is called
Double Covalent Bond:
When each bonded atom contributes two
electrons two bond pairs are sharedand a double covalent bond is formed , These bond pairs are indicated as double line between of such molecules the molecules like oxygen (O2) gas and ethane (c2H2) show such typeof double covalent bonds
Triple Covalent Bond:
When each bonded atom contributes three electrons, three bond pairsare involved in bond formation
. this type is called convalentbond. Three small line are used to indicatethese three pairs of electron between those atoms in the molecules of such compounds .The example of molecules having triple covalent bonds are nitrogen (N2) and ehyne*C2H2)
By this mutual sharing of valence shell electrons each of the contributing
atom attains the octet or nearest noble gas electronic configuration
What is chemical bond and why do atoms form chemical bond?
Definition: chemical bond is defined as force of attraction between atoms that holds them together in a molecule or a compound.
During the bond formation there is some force which holds the atoms together is called chemical bond.
It is universal rule that everything in this world tens to become more stable. Atoms achieve stability by attaining electronic configuration of inert gases( HE, Ne or Ar, etc.) i.e. ns2,ns2np6 . Having2 or 8 electrons in the valance shell is the sign of stability . Attaining two electrons in the valence shell is called duplet rule. While attaining eight electrons in the valence shell is called octet rule.
Atoms can accommodate 8 electrons in its valence shell in three-way
- By giving valence electrons ( if they are les than three) to other atoms.
- By gaining electrons from other( if the valance shell has five or more electrons in it) atoms
- By sharing valence electrons with other atoms.
How chemical bond is formed?
When two approaching atoms come close the attractive as well as repulsive force becomes operative. The formation of chemical bond is the result of net attractive force which dominates. The energy of that system is lowered and molecule is formed. Otherwise if repulsive forces become dominate the chemical bond will not form . IN that case there will be increase in energy of the system due to creation of repulsive forces.
What is an ionic bond? explain in detail with example
Ionic bond is type of chemical bond which is formed by the complete transfer of electrons from one atom to another.
What is covalent bond? write its types ? explain with examples.
Covalent bond: the bond which is formed due to mutual sharing of electrons is called covalent bond.
Explanation; the energy changes during the covalent bond formation are of considerable value. When two atoms approach each other attractive forces develop between electrons of one atom and nucleus of other atom. Simultaneously repulsive force between electrons of the two atoms as well as between their nucleus also created. When the attractive forces dominated due to decrease in distance between those two atoms a chemical bond is formed between them. The formation of hydrogen, chlorine and oxygen gases are few example of this type of bonding.
Bond pair: the electron that pair up to form a chemical bond are called bond pair electrons.
Explain dative covalent or coordinate covalent bond
Dative covalent or coordinate covalent bone: coordinate covalent or dative covalent bonding is a type of covalent bonding in which the bond pair of electrons is denoted by one bonded atom only.
How polar and non polar covalent bonds formed?
Non polar covalent bond: if a covalent bond is formed between two similar atoms (homo-atoms) the shared pair of electrons is attracted by both the atoms equally. Such type of bond is called non polar covalent.
Example: the bond formation in H2 and Cl2 is an examples of nonpolar covalent bond.
What are intermolecular forces? explain dipole dipole interactions.
Intermolecular forces: the relatively weak forces of attraction between molecules that holds the molecules together are intermolecular forces.
Vander Waals forces: all intermolecular forces , which are collectively called Van der Waals forces.
What are hydrogen bonding explain in water.
Definition: partially positively charge hydrogen atom of one molecule attracts and forms a bond with the partially negatively charged atom of the other molecule, the bonding is called hydrogen bonding.
What are properties of ionic compound
Properties of ionic compound : ionic compounds a re made up of positively and negatively charged ions. Thus they consist of ions and not the molecules. These positively and negatively charge ions are held together in a solid or crystal form with strong electrostatic attractive forces . The orderly arrangement of Na+ and Cl- ions in a solid crystal of sodium chloride.
Explain the properties of covalent compounds.
Properties of covalent compounds: The covalent compounds are made up of molecules that are formed y mutual sharing of electrons between their atoms i.e. covalent bonds. A covalent bond is generally regraded as weaker than an ionic bond. Covalent compounds are made up of two or more non-metals. Low mass covalent compounds are gases or liquids. Contrary to it, higher molecular mass covalent compounds are solids. General properties shown by covalent compounds are as followLow melting and boiling pointBad conductorInsoluble in waterstable and hard
What are main properties of metals
Properties of metal:
- Metallic luster: they show metallic luster
- Malleable and ductile: they are usually malleable and ductile. Malleability is the property by virtue of which metals can be drawn into sheets while ductility is the property virtue of which a metal can be dawn into wires.
- High melting and boiling point: they have usually high melting and boiling points
- Low ionization energies: being greater in size they have low ionization energy
- Good conductor: they are good conductor of heat and electricity in solid and liquid state due to mobile electrons.
Give properties of coordinate covalent compounds
Properties of coordinate covalent compounds: the properties are given below
- Similar to covalent compounds: their properties are mostly similar to those of covalent compounds.
- Shared pair: Nuclei in coordinate covalent compounds are held by the shared pair of electrons
- Formation of ions: coordinate covalent compounds do not form ions in water
- Solution in organic solvents: coordinate covalent compounds do not form ions in water , due to their solvent nature they form solution inorganic solvents.
- Less soluble water; coordinate covalent compound are very less soluble in water
- Rigid compounds: usually coordinate covalent compound are rigid.
What is metallic bond? explain
Definition: the metallic bond is defined as a bond formed between metal atoms ( positively charged ions) due to mobile or free electrons.